New OS (5) Auto-Rebuild not working

I have a PR2100 with two 8tb drives set up as a Raid 1 mirror. I have a 3rd drive. About once a month I swap a drive and one goes into a fire safe - so I have my mirror and an additional backup that is up to a month old. When I swap in the older drive (which is 98% up to date typically) Auto-Rebuild does nothing. Have tried rebooting the system which also does not do anything. OS upgraded more than one swap ago. Is that lack of action from Auto-Rebuild intentional? If so what is the function of Auto-rebuild? Manual rebuild (experience), which wipes the disk and starts again, takes the system more than 24 hours typically with about 5tb of data. During that time, we can use the drive but if we do it dramatically increases re-population time on the swapped in drive which increases the pain - the present update is 25 hours in and claims it needs another day to complete because we’ve used the drive. This storage system and the backup drive is our only record of everything we have done in our lives - we’ve scanned everything and destroyed the paper filing cabinets that we used to have so the backups and the spare in the fire safe is important to us. What I would like is a faster, reliable. Each monthly rebuild is becoming more painful as the storage used increases. We could happily accept an overnight rebuild but more than a 24 hour day feels excessive. Help!

Hi @Willem1,

Thanks for reporting the issue.

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